The previous Bangladesh government headed by Sheikh Hasina was behind systematic repression and killings of protesters last year, the United Nations said in a report on Wednesday, suggesting that the abuses could amount to “crimes against humanity”.

Hasina fled to India on August 5 after several weeks of widespread student-led protests against her Awami League government. She had been the prime minister of Bangladesh for 16 years.

Nobel laureate economist Muhammad Yunus took over as the head of Bangladesh’s interim government three days later.

The Hasina government, the country’s security and intelligence services and “violent elements” associated with the Awami League party “systematically engaged in a range of serious human rights violations” during the agitation in July and August, the UN Human Rights Office said on Wednesday.

Publishing findings of its fact-finding inquiry into the events, the UN agency said that it found an “official policy to attack and violently repress anti-government protesters”. The crimes require further criminal investigation, it added.

A team of the UN human rights agency had been sent to Bangladesh in September at the request of Yunus for independent fact-finding into the events.

Of the 1,400 killed and thousands injured between July 1 and August 15, the vast majority were shot by Bangladesh’s security forces, the report said. Of these, 12% to 13% killed were children.

UN Human Rights chief Volker Türk said that the “brutal response” to the protests was a “calculated and well-coordinated strategy” by the Hasina government to hold on to power.

Türk said that there were reasonable grounds to believe “hundreds of extrajudicial killings, extensive arbitrary arrests and detentions, and torture” were carried out with the knowledge, coordination and direction of the country’s leadership.

He said that testimonies of senior officials and other evidence “paint a disturbing picture of rampant state violence and targeted killings, that are amongst the most serious violations of human rights, and which may also constitute international crimes”.

“Accountability and justice are essential for national healing and for the future of Bangladesh,” he added.

Bangladesh’s International Criminal Tribunal has filed three cases and issued two warrants for the arrest of Hasina and her associates, including former military generals and an ex-police chief, for their alleged role in enforced disappearances, among other alleged crimes.

The first warrant was issued in October on charges of committing crimes against humanity during the protests that toppled the Hasina government.

The Awami League regime under Hasina had long faced allegations of enforced disappearances. However, the former prime minister consistently denied the accusations.

On February 6, Dhaka said that legal processes were underway to extradite Hasina and others from India.